This is the shocking and really wrenching video gone viral of New York City police tackling a man on the street. They say he was resisting arrest for illegally selling cigarettes. Five police tackling him and Eric garner who repeatedly complained he couldn't breathe suffered a heart attack and died at the hospital. The mayor is promising a full investigation as Ron is here with more on the story. Hard to watch that video. Bianna, not just growing outrage but growing controversy over this incident which took place on New York City's Staten island. The suspect in a tense standoff with two police officers who were trying to arrest him then a struggle and an hour and a half later that suspect dead at a local hospital. Now come questions, did police follow standard arrest procedure or did they go too far? This video taken by a bystander capturing the drama as it unfolds. Let go. Watch. It shows two plainclothes police officers confronting 43-year-old Eric garner, his crime, allegedly selling loose cigarettes. I'm minding my business. Please leave me alone. Reporter: Finally the officers try to physically arrest him. Garner appears to resist. One officer puts his forearm around garner's neck as other officers join in to wrestle the man down from the ground garner cries out -- I can't breathe. I can't breathe. His eyes rolled back of his head and then he just was not responding whatsoever. Garner was taken to a local hospital where he was pronounced dead about an hour later. His cause of death unknown. Nobody should have to die while being arrested. But Mr. Garner's medical condition may have been the cause of it and not the action of the officers. Reporter: The mother of garner's infant daughter anguished and angry. They murdered him. They hurt him. They killed him, you know. New York police commissioner William Bratten acknowledges the video appears to show a police officer applying a choke hold on garner, a move prohibited in the NYPD. It is defined this would be a choke hold. Reporter: Now police and prosecutors work to find out why this arrest resulted in the suspect dying. New York City's mayor says he calls it troubling. He was supposed to leave for vacation but postponed it for one day and on Staten island protests over the incident are planned led by the activist Al Sharpton all of this while police internal affairs investigators and prosecutors launch separate investigations into what exactly happened. The mayor trying to simmer tensions down. This is going to be tense for awhile. A lot of questions. Thanks. Coming up on "Gma" the most

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